Pradosh Vrat, or Pradhosham, is an important fasting day dedicated to Lord Shiva. Pradosha occurs twice in a month – on the 13th day (Trayodashi) – during the waxing moon fortnight and the other during the waning moon fortnight. The puja and worship is done in the evening. The Pradosha period can be loosely indicated as 1.5 hours before sunset and 1 hour after sunset.

The Shiva Purana states that one undertakes fasting on Pradhosha will be blessed with wealth, children, happiness and honor. The fasting and worship is specially undertaken by women who long to have children. It is said that those praying to Shiva during the auspicious time of Pradhosha will be freed from sins.

There are numerous legends associated with the Pradhosha Vratam. It is believed that Lord Shiva drank the Halahala poison that was churned up from the Ocean of Milk (Samudra Manthan) during Pradosham.

Another myth indicates that Lord Shiva and Parvati, the divine couple, are in a propitious mood during the evening twilight on the Trayodashi day and hence are easily pleased and grants whatever that a sincere devotee asks.

Offering Bael or Bilva leaves during the period to Lord Shiva is considered auspicious.

There are Shiva devotees that observe fast on both Pradosha days in a month. Some only fast during the waning phase of moon.

Staunch devotees opt for water only fasting and will only eat the ‘prasad’ offered in the evening. Such devotees only eat cooked from next day morning.

Another method of fasting is by eating fruits and such devotees eat cooked food on the day after the evening prayers. The strictness of the Pradosha fasting is usually decided by the devotee.

Some devotees do not fast but worship Shiva during the period or visit temples.

Since Monday is dedicated to Shiva, the Pradosha falling on Monday is referred as Soma- Pradosha and is considered highly auspicious. Pradosha falling on Saturday during the waning phase of moon is also auspicious.